1. Field of the Invention
The present invention relates to a method and an apparatus for a single facer glue application adjustment in which a glue application roll is adjusted of its setting position based on a variation in vibration, noise, drive torque or pressing reaction force of the glue application roll.
2. Description of the Prior Art
A belt pressing type single facer in the prior art is described with reference to FIG. 5. Numeral 1 designates a glue application roll, numeral 3 designates a doctor roll, numeral 4 designates a glue tank forming a wall on one side by the glue application roll 1 and the doctor roll 3, numeral 2 designates a glue within the glue tank 4, numeral 7 designates a glue application portion unit supporting the glue application roll 1, the doctor roll 3 and the glue tank 4, numeral 9 designates a downstream side corrugating roll (an upper corrugating roll), numeral 12 designates an upstream side corrugating roll (a lower corrugating roll) contra-rotating in engagement with the downstream side corrugating roll 9, numeral 11 designates a core paper, numeral 15 designates an endless belt pressing touchingly the downstream side corrugating roll 9, numeral 13 designates a single faced corrugated board sheet, numeral 14 designates a liner, thus a glue application apparatus of a belt pressing type single facer is constructed by the glue application roll 1, the doctor roll 3 and the glue tank 4.
In the belt pressing type single facer in the prior art shown in FIG. 5, the core paper 11 is led between the upstream side corrugating roll 12 and the downstream side corrugating roll 9 engaging and contra-rotating each other to be corrugated into a wave-shaped state and then this core paper 11 is led between the glue application roll 1 and the downstream side corrugating roll 9.
Then, in the glue application apparatus, the glue 2 within the glue tank 4 is applied to the outer circumferential surface of the rotating glue application roll 1, is adjusted to form a glue film of a predetermined thickness by the doctor roll 3, is transferred rotatingly to the direction of the downstream side corrugating roll 9 and is coated on the tip portions of corrugations of the core paper 11.
Said core paper 11 and the liner 14 supplied via another route are led between the endless belt 15 and the downstream side corrugating roll 9 to be lapped each other and, with a predetermined pressing force P and temperature, the core paper 11 and the liner 14 are bonded by the glue 2 coated on the tip portions of corrugations of the core paper 11, thus the single faced corrugated board sheet 13 is produced.
FIG. 6 shows an example of a gap adjusting apparatus in the prior art for adjusting a gap between the downstream side corrugating roll 9 and the glue application roll 1. Numeral 16 designates a frame, numeral 27 designates a cylinder mounted on the frame 16 and a piston rod of the cylinder 27 is supported pivotally by the glue application portion unit 7.
Numeral 28 designates a positioning metal element fixed to the glue application portion unit 7, numeral 30 designates an eccentric shaft and numeral 29 designates a stopper supported by the eccentric shaft 30.
In the gap adjusting apparatus shown in FIG. 6 for adjusting the gap between the downstream side corrugating roll 9 and the glue application roll 1, the cylinder 27 is moved to the direction of elongation, the positioning metal element 28 is hit to the stopper 29, thus the gap between the downstream side corrugating roll 9 and the glue application roll 1 is set to a predetermined measure.
If the gap between the downstream side corrugating roll 9 and the glue application roll 1 is to be adjusted in the above-mentioned state, the eccentric shaft 30 is rotated, the stopper 29 is moved to the right or left in the figure, the positioning metal element 28 and the glue application portion unit 7 are moved in same direction and the gap between the downstream side corrugating roll 9 and the glue application roll 1 is finely adjusted.
Incidentally, as a roll gap adjusting apparatus not shown in the figure, there is one in which an insertion amount of a wedge-like element inserted between the stopper 29 and the positioning metal element 28 is changed, a stopping position of the glue application portion unit 7 is changed, thereby a gap between the downstream side corrugating roll 9 and the glue application roll 1 is adjusted.
FIG. 7 shows another example of a gap adjusting apparatus in the prior art for adjusting a gap between the downstream side corrugating roll 9 and the glue application roll 1. This roll gap adjusting apparatus is constructed so that the glue application portion unit 7 supporting the glue application roll 1, the doctor roll 3 and the glue tank 4 is moved up and down by a cylinder 21, thereby the glue application roll 1 and the downstream side corrugating roll 9 can make contact or separation each other, and at the stroke end position of the cylinder 21, the gap between the glue application roll 1 and the downstream side corrugating roll 9 is set at a predetermined measure corresponding to a thickness of the core paper 11.
The gap adjusting apparatus in the prior art shown in FIG. 6 is constructed so that the cylinder 27 is moved to the direction of elongation, the positioning metal element 28 is hit to the stopper 29, thus the gap between the downstream side corrugating roll 9 and the glue application roll 1 is set to a predetermined measure.
Further, the gap adjusting apparatus in the prior art shown in FIG. 7 is constructed so that the glue application portion unit 7 supporting the glue application roll 1, the doctor roll 3 and the glue tank 4 is moved up and down by the cylinder 21, thereby the glue application roll 1 and the downstream side corrugating roll 9 can make contact or separation each other, and at the stroke end position of the cylinder 21, the gap between the glue application roll 1 and the downstream side corrugating roll 9 is set at a predetermined measure corresponding to the thickness of the core paper 11.
Accordingly, in order to make a state of glue transfer uniform in a case of change of thickness of a core paper accompanying with change of orders, it is necessary to make the roll-gap adjustment manually at each time of change of orders, and moreover as the adjustment is troublesome and a long time is needed for re-setting, there is such a problem that an operation efficiency of a single facer is lowered.
Further, there are such shortcomings that due to negligence or failure of said re-setting, for example, in case of a changed core paper 11 becoming thicker, a pressing force acts on the core paper 11 so that the core paper 11 tears, or in case of a changed core paper 11 becoming thinner, the gap increases so that a glue transfer amount becomes less.